Hydraulic built-in jack



March 14, 1944'. c. H. SMITH HYDRAULIC BUILT-IN JACK Filed May 4, 1942 2 Sheets-Sheet 1 grwq/wtom 6771527? March 14, 1944. c. H. SMITH 2,343,937

HYDRAULIC BUILT-IN JACK Filed May 4. 1942 2 Sheets-Sheet 2 cZYde Hwrc urz 7!? Patented Mar. 14, 1944 UNITED STATES PATENT OFFICE 2,343,937 nrnaauu'c BUILT-IN JACK Clyde Harcourt Smith, Panama City, Panama Application May 4, 1942, Serial No. 441,661

1 Claim.

This invention relates, to a vehicle jacking sys tem for raising one or more wheels of the-vehicle.

The main object of this invention is to provide a simple and highly efllcienthydraulic jack means mounted on a vehicle in proximity to all of its ground wheels and power operated from the vehicle engine, all of the jack means being connected to a common reservoir and valve housing and each jack means being selectively operated from the vehicle dash. there being further provided an electrical control system for the valve means and other operating parts of the hydraulic system.

With the foregoing and other objects in view, the invention resides in the novel arrangement and combination of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention'herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention. I

A practical embodiment of the invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a plan view of an automobile or truck chassis showing hydraulic jack mounting. hydraulic mechanism and electric control.

Figure 2 is an elevational view of rearaxle showing hydraulic jack mounting thereon.

Figure 3 is a sectional view through one of the hydraulic jacks mounted on the rear axle, showing same in extended operative position, and also showing diagrammatically the hydraulic operating and electrical control system therefor.

Referring to the drawings wherein like reference characters indicate like parts throughout. i0 denotes a vehicle chassis comprising a front axle II, a rear axle l2, an engine l3, transmission l4 and drive shaft i5.

Carried by each axle and adjacent each of the wheels thereof are the hydraulic jacks l6, l1, l3 and I9, respectively connected by conduits20, 2!, 22 and 23 to a. distributive chamber or valve housh1g2, which in turn is connected by a delivery conduit 25 and return conduit 26 to a reservoir 2i, there being interposed in the delivery conduit 26 a pump 28.

As each of the jacks are identical in construction a description of one will sufiice. Referring to Figure 3 the jack I6 is shown to comprise three telescoping cylinders an, 3| and 32. The outermost cylinder 30 is provided at its upper end which is closed with an arcuate flange 33 adapted for guiding engagement with the cylinder 3i. The intermediate cylinder 3| is open at both ends and is provided at its upper end with a radial flange 31 adapted to limit outward movement of the cylinder when it comes into engagement with the packing 35. At its lower open end the cylinder 3! is provided with a packing 33 and guide sleeve 39 similar to the packing and guiding sleeve of cylinder 30. The inner or lowermost cylinder 32 is open at its upper end which is provided with a limiting flange 40 adapted to engage the packing 38 of intermediate cylinder 3|. The lower end of the cylinder 32 is closed and is provided with an integral reduced diameter threaded extension 42 provided with spherical bearing socket 43 adapted to receive the ball end 44 of the jack ground engaging abutment 45. The ball end 44 is provided with a stem 46 which is secured to the abutment 45 by the screw 41. A locking sleeve 48 fitted in the threaded extension 42 serves to retain the ball end N in bearing engagement with its socket 43. It is thus apparent that the abutment 45 is capable of assuming different positions depending on the contour of the ground. A tension coil spring 50 is arranged within the telescoping cylinders, and has its upper end secured by means of clips 5| (only one of which is shown) to the head end of the cylinder 30, the lower end of the spring 50 having hooked engagement with a lug 52' provided on the lower closed end of the cylinder 32. The coil spring 50 is so designed as to telescope the cylinders one into'the other and to retain the same in their collapsed inoperative position such as shown in Figure 2.

With relationto the front axle H suitable means (not shown) connectithe jacks I8 and i9 thereto. Each of the upper head ends of the outer cylinders 30 of the jacks are provided with a passage 55 for communication with the interior of the cylinders and to each of which the conduits 20, 2!, 22, and 23 are respectively connected.

Suitably located on the chassis i0 is the reservoir 21 containing a suitable liquid for use in the hydraulic system such as oil or any other liquid medium having the characteristic of nonfreezing and free flowing in all kinds of weather. A rotary pump 28 is driven by a power take off shaft 58 operable in a manner to be hereinafter described. It is to be understood that any type of the lack I8.

lief chamber I4.

that the form shown hereinand described is only for purposes of explanation. Connecting the reservoir 2I'and pump 28 is one section 28a of the delivery conduit 28 the other section 28b thereof connecting the pump and the distributing chamber 24.

The valve housing 24 comprises a two-part casing 88 in which are positioned four valves only one of which is shown and as they all are identical only one will be described. This valve 8| is mounted on the end of a valve stem 82 which extends outwardly of the casing 88. The remaining valves are respectively carried by the stems 83, 84 and 88. The valve 8| is adapted to seaton a valve seat 88 and is normally held seated thereon by the coil spring 81. The valve seat 88. is formed on the inner end of a passage 88 in which is located one end of the conduit 28 the other end thereof being fitted in the passage 88 In a like manner the other conduits 2|, 22 and 23 connect the respective valve controlled passages with the passages in the jacks I1, I! and I8. Thus, fluid delivered into the valve housing 24 is by-passed to the Jacks when the valves are opened in the manner to be hereinafter described. In Figure 3, it is seen that the valve 8| is open so that the fluid is bypassed into the conduit 28 to be delivered into Provided in the valve casing 88 is a'pressure relief ball valve I8 normally closing the passage II and held in this position by a spring 12 the tension of which may be adjusted by the screw I3, the whole being mounted in the pressure re- The return conduit 28 has one end connected to the chamber I4 and its other end with the reservoir 21, thus, when the cylinders of the jack I8 are fully expanded no more liquid can be delivered thereto. The back pressure thus set up opens the relief valve I8 against the adjusted tension of the spring 12 enabling the .liquid delivered by the pump 28 to flow through passage 'II into the chamber I4 and out through return conduit 28 back to the reservoir. The relief valve I8 is operative regardless whetherone, any'number of or all the Jacks are simultaneously placed into operation.

The jack operating valve 8| is operated by a solenoid I8 and the other jack valves are respectively operated by the solenoids 11, I8 and I8. Provided on the vehicle dash convenient to the operator is a switch panel 88 provided with switches 8|, 82, 83, 84 respectively controlling the solenoids I8, 11, I8 and I8. Current is supplied from a battery 88 by conductors 81, 88, 88 and 88 to one terminal of the solenoids there being interposed in said conductorsthe switches 8|, 82, 83 and 84, the other terminals being connected to a ground return by conductors 8|, 92, 83 and 84.

A conductor 85 connects the battery with one terminal of the magnetic clutch 88 in which conductor is interposed a switch 88, the other ter- With the pump 88 in operation and assuming that it is desired to-operate jack I8. the same is rendered functionally operative by closing switch 8| whereupon the solenoid I8 will be energized to move valve stem 82 and valve 8| upwardly off its seat 88 to thereby by-pass the liquid delivered into the valve housing 24 through the conduit 28 into the cylinders of the lack I8 to expand the same outwardly. During this operation the relief valve 18 will :be closed and will only open again when the Jack I8 is fully extended in the manner as hereinabove described. At the same time should it be desired to utilize any one of the other.iacks, the same may be operated by the closing of the switch controlling the solenoid operating the valve controlling the operation of said jack.

When it is desired to permit a jack to contract or collapse to its inoperative position. it becomes necessary to remove from the extended jack a quantity of liquid. This is'automatically accompli'shed by operation of the jack collapsing control. Provided in the valve casing 88 is a branch conduit I88 which communicates the interior of the valve housing with the return conduit 88. The branch conduit I88 is opened and closed .by a spring pressed valve |8| that is operated by a solenoid I82. Current is supplied to one terminal of the solenoid I82 by a conductor |88, the other terminal being connected to a ground return by the conductor I84. interposed in the conductor I83 is a pair of switch contacts adapted to be engaged by the switch element of the pump clutch switch 88. In fact the switch 88 is of the twoway type, in one closed position it closes the sin cuit to the magnetic switch 88 and in its other closed position it closes the circuit to solenoid Thus to collapse the Jack I8, the magnetic I clutch circuit is brokenby operation of the switch minal being connected to a ground return by a 88 which thus stops the pump 28 and the delivery of liquid to the valve housing 24. The switch 88 is then moved to its other position to close the circuit to solenoid |82 whichthus becomes ener- Sized opening valve I 8|. The Jack valve 8| is held open during this operation by keeping the switch 8| closed. As there is now no pressure in the hydraulic system the contracting force of coil spring 58 is sufficient to contract the cylinders 3| and 82, the liquid therein be forced back through conduit 28 into valve housing 24, through branch conduit I88 into return conduit 28 back to reservoir 21, this continuing untilv the cylinders of the jack I8 are completely collapsed and the Jack assumes its inoperative position, see Figure 2. The switch 8| may then be opened and the entire system is now in inoperative position.

Having described the invention and the maniner in which the same operates-what is claimed hicles comprising an hydraulic jack mounted on the vehicle adjacent each wheel, a reservoir containing a supply of fluid, a distributing chamber, a pump for delivering fluid under pressure from said reservoir to said distributing chamber, a power take-oil shaft connected to the vehicle transmission for driving said pump, a magnetic clutch between said shaft and pump, a connection from said distributing chamber to each of said Jacks, a solenoid operated valve for each connection operable within said distributing chamber, and remote control switch means for operating said clutch and for selectively operating said valves whereby to permit the delivery of said fluid either to all of said lacks, any selected group An hydraulic jack system for automotive vein said return connection operable to permit a 10 return of the fluid back to said reservoir when said jack is contracted to its inoperative position, a two-way pump clutch switch connected to said magnetic clutch and to said return valve solenoid, said switch in one closed position closing the circuit to said magnetic clutch and in its other closed position closing the circuit to said return valve solenoid and opening the circuit to said magnetic clutch.

CLYDE HARCOURT SMITH. 

